We show time-resolved measurement of Raman gain in Silicon submicron-size planar waveguide using picosecond pump and probe pulses. A net nonlinear gain of 6 dB is obtained in a 7-mm long waveguide with 20.7-W peak pump power. We demonstrate an ultrafast all-optical switch based on the free-carrier dispersion effect in the silicon waveguide, whose transmission is enhanced by more than 13 dB due ...

In this paper we pose the question: After gathering N data points, at what value of the control parameter should the next measurement be done? We propose an on-line algorithm which samples optimally by maximizing the gain in information on the parameters to be measured. We show analytically that the information gain is maximum for those potential measurements whose outcome is most unpredictable...

Multiresolution ESPRIT is an extension of the ESPRIT direction finding algorithm to antenna arrays with multiple baselines. A short (half wavelength) baseline is necessary to avoid aliasing, and a long baseline is preferred for accuracy. The MR-ESPRIT algorithm allows the combination of both estimates. The ratio of the longest baseline to the shortest one is a measure of the gain in accuracy. B...

A 100-element quasi-optical amplifier is presented. The active devices are custom-fabricated modulation-doped field-effect transistors (MODFET’s). Common-mode oscillations were suppressed using resistors in the input gate leads. The grid has 9 dB of gain at 10.1 GHz. The 3-dB bandwidth is 1.2 GHz. We present a model for the gain of the grid versus frequency and compare measurement with theory.

Photonics-assisted microwave instantaneous frequency measurement (IFM) is considered as a promising technique for detecting an unknown radio-frequency (RF) signal, which has advantages of broad range and fast processing speed. Up to date, there no photonics-assisted IFM system that can essentially measure RF signal time-frequency information with power fluctuating seriously. Moreover, the accur...

One of the jobs of a circuit designer is to build a measurement system that provides valid input-to-output data as defined by the system requirements over a given frequency range. The four possible elements of a signal path include a gain/signal conditioning cell, an anti-aliasing filter, an analog-to-digital converter (ADC) and a digital processing block. Figure 1 shows this type of system wit...

This study investigated the baseline predictors of best corrected visual acuity (BCVA) and central retinal thickness (CRT) at 6 months in patients with treatment-naïve branch retinal vein occlusion (BRVO) and central retinal vein occlusion (CRVO). This multicenter, interventional case series included 208 BRVO and 123 CRVO patients with follow-up period of 6 months or more. Outcome measures of B...